As Media Matters previously reported last October about Richard Mack, leader of the Constitutional Sheriffs and Peace Officers Association:

Mack is a former Arizona county sheriff and the founder of the Constitutional Sheriffs and Peace Officers Association, an organization which subscribes to the ideology that sheriffs “should be the ultimate law enforcement authority in the U.S.” The organization claims that sheriffs have the “Constitutional authority to check and balance all levels of government,” superseding “any agent, officer, elected official or employee from any level of government when in the jurisdiction of the county.” Constitutional scholars and other experts dispute this assertion, with some noting that the Constitution doesn’t mention sheriffs at all.

Mack and CSPOA have pushed for sheriffs to get involved with mass deportation efforts, even holding the organization’s November national conference in Washington state in part because its attorney general is suing a sheriff for aiding the Trump administration’s deportation efforts. Mack also said he has been talking to Homan about “getting sheriffs involved in deportation.”